body {
    background-image: url(../img/bg.jpg);
    background-repeat: no-repeat;
    background-size: cover;
    display: flex;
    justify-content: center;
    align-items: center;
    align-content: center;
    height: 100vh;
}

form {
    width: 300px;
    height: 350px;
    display: flex;
    flex-direction: column;
    padding: 10px;
    background-color: rgba(255, 255, 255, .5);
    box-shadow: 7px ​11px 15px rgb(0 0 0 / 50%);
    border-radius: 5px;
}

form>* {
    margin-bottom: 20px;
}

form>h2 {
    text-align: center;
}

#file {
    width: 200px;
    display: inline-block;
}

form>div:nth-of-type(2)>label {
    position: relative;
    top: -30px;
}

form>div:first-of-type {
    position: relative;
}

#name {
    padding: 10px 20px;
    border: none;
    border-bottom: 1px solid;
    outline: none;
    box-sizing: border-box;
    width: 200px;
    background-color: transparent;
}

#tips {
    position: absolute;
    top: 9px;
    right: 17px;
}

.subBtn {
    position: relative;
    top: 20px;
    margin: 0 auto;
    width: 200px;
    height: 30px;
    outline: none;
    border: none;
    background-color: rgba(255, 255, 255, .3);
    box-shadow: 9px 6px 10px rgb(0 0 0 / 34%);
    transition: all .3s;
    border-radius: 10px;
}

.subBtn:hover {
    transform: translateY(3px);
    background-color: rgba(255, 255, 255, .5);
    box-shadow: 3px 2px 5px rgb(0 0 0 / 50%)
}